Telephone-exchange system



' H.-P. CLAUSEN ET AL TELEPHONE EXCHANGE SYSTEM Filed July 19 1919 *3 t q i S I I I /n yen/ans fienryf Clause/'2 (ha/4&5 L. Gym/rum W A/fy.

Fate-rated Jan. 8, 19.2

HENRY P. OLAUS-EN, OE MOUNT VERNON, AND CHARLES Ii. GOODRUIVI', OF,- NEW YORK,

N. Y., ASSIGNORS TO VJ'ESTERN ELECTRIC COMPANY, INCOBBOBATED, A CORIGR A- TION OF NEW YORK.

iaaraa TELEPHONE-EXCHANGE, SYSTEM.

Application filed July 19, 19-19.,

To all whom it may concern:

Be it known that we, HENRY P. CLAUsEN and Gratuities L. GOODRUM, citizens of the United States, residing at Mount Vernon,.in the county of vi estchester and State of New York, and at New. York, in the county of Newv York and State. of New York, respectively, have invented certain new and useful Improvements in Telephone-Exchange Systems, of which the following is afull, clear, concise, and exact description.

This invention relates to improvements in telephone exchange, systems and has particular reference to a special service feature therefor.

It is desirable, especially during certain times, that incomingcalls to aprivate automatic exchange should be connected to the desired substation and also to a special attendants position in such manner that the attendant may ascertain if the called sub scriber answers and, if not, then converse with, the calling party.

An object of the invention is to provide means whereby a special attendantsposition may be caused to be connected, during certain hours, to an established connection.

In accordance with this object, a time controlled mechanism is operable, when a calling line is connected to a. called line, to cause an auxiliary trunk. hunting switch at an attendants position to connect the at tendants substation apparatusto the calling and called lines. A. signaling current is then simultaneously applied to the called and the attendants substation and the attendant may first determine without affecting the connection whether or not the called party answers. If not, the attendants line may then be connected to the calling line to permit. the attendant to converse with the calling party.

The inventive idea involved is capable of receiving. a variety of expressions one of which, for the purposeof illustrating the invention, is shown in the accompanying drawing; but itis to be expressly understood that said drawing is. employedmerely for the purpose of. facilitating the description of the-invention as'awhole and not to define the limits "thereof, reference being had to the appended claims for this purpose.

In the drawing, the figure illustrates Serial No. 311,958;

the called party/answers andif he does not,

then converse with the calling party. In order. to, accomplish th s-pu pose, us s met erably made of a trunkhunting switch 1*) operated by mechanism F tohunt for the calling andcalled lines... The. mechanism F is preferably associated with a clock. (not shown) and made common to a plurality of switches C. This mechzmisinv comprises.

an annular conducting. member f and. in-

dividual conducting, segments f correspond ing-in number to the hoursof the day, The grounded wiper f is adapted tofengage segments andby insertinga plug or. plugs f between one or a, number, of, segments 7 and the annular conducting member. it will'be: apparent that'when the wiper f en, gages segments. 74 the ground will, be appliedto conductor- When one. of the connector switches. is. operated, the ground, on this conductor. isextended totheswitch E andcausesthe same tohunt for thecalling and called lines and upon findingthesame signaling current will be simultaneously, ap-

. plied to substations B and D. The attendant at substation D may then respond, and t listen into determine whether or; not; the called subscriber, answers.

1t is believed that the invent-ion-will'ncw be fully understood from the following detailed (ilescriptionof the operation,. i llhen a subscriber at substitution A initiatesa call,

automatic switches, such as one eonrerr.

tionallzv shown at G are operated in a, manner. well-known inthe art to extend the-calling line to one ofthe'connector switches G. Connector switch (J is similar iniits operation to the connector switch shown in the patent to Goodrum $51,231,013 issued; June,

26, 1917. A circuit is then established. for line relay 1 of the selected switch C which circuit is traceable from grounded battery, right winding of relay 1, brush 2, apparatus at substation A, brush 3 and left winding of relay .1 to groun d. Relay 1, in energizing establishes a. circuit for slow-to-release relay 4, and at its back contact and armature removes the ground from the third wire and brush 18 which had up to this time marked the switch as idle. The switch is now in position to receive the impulses correspond ing to the tens digit of the wanted line and in response to the first impulse, relay 1 retracts its armature to establish a circuit for slow-to-release relay 5 extending from grounded battery, windii'u: of said relay, front contact and right armature of relay 4 and back Contact and armature of relay .1 to ground. Relay 5 energizes and establishes a. circuit for escape magnet 6 extending; from grounded battery, front contact and right armature of relay 5, winding of magnet 6 and back contact and armature of ringing relay 7 to ground. Relays 4 and 5 maintain their armatures attracted during the transmission of impulses. In response to each interruption in the line, a circuit is established for primary stepping magnet 8 extending from grounded battery, winding of said magnet, side-switch wiper 9 in position 1, front contact and right armature of relay a and back contact and armature of relay 1 to ground.- Magnet 8 operates to step brushes 10-, 11 and 1.2 of switch C in a group selecting movement. At the termination of the first set of impulses, relay 1 remains energized and opens the circuit for relay 5 which, upon releasing, breaks the energizing circuit for escape magnet 6. This magnet then releases and moves the side-switch wipers into position 2. The

- second set of impulses now transmitted will operate the secondary stepping magnet 13 over a circuit extending from grounded battery, winding of said magnet, side-switch wiper 9 in position 2 and from thence over the previously described circuit to ground at the armature of relay 1. Relay 5 again releases to open the energizing circuit of cscape magnet 6, but if the called line busy this magnet, being; slow to release. will not deenergize before a circuit established for the release magnet 14. This circuit is t raceable from grounded battery. right winding" of said magnet, right armature and back contact of relay 15, oitnornal contact 16 which closes upon the first step ot the switch, left armature and back contact of relay 5, side-switch wiper 16 in position 2, brush l2 and terminal 17 to ground. llflagnet 1-1- loclrs up over a circuit extending from ground, left winding of said magnet, left armature and front contact of said trout contact and. left armature of relay 4 brush .18, to grounded battery at a. preceding switch such as shown in Fig. 2 of the above mentioned patent granted to (l. L. Goodrum. In energizing, magnet 1 1 operates to return switch C to normal position and at the same time applies a busy tone to the calling subscribers line. The callino' subscriber upon hearing the busy tone, replaces his receiver upon its switchhook and thereby restores the other switch or switches in a well-known manner.

Assuming that the called line is idle, and that at the time the call is made, there is no ground upon conductor f magnet 14 will fail, to energize upon the release of relay 5 and escape magnet 6 will therefore decncrgize to more the side-switch wipers into position 3. A circuit will then be established for relay 5 extending from grounded battery, windin v of said relay, side-switch wiper S in position 3 and front contact and armature of relay 1 to ground. Relay 5 again establishes an energizing circuit for escape magnet 6 but the side-switch Wipers will remain in position 3. Energization of magnet 6 applies ringing current from a suitable source through the front contact and armature of magnet 6, winding of relay 7, side-switch wiper 19 in position 3, brush 11, apparatus at substation B including the ringer, brush 10, side-switch wiper 20 in position 3, front contact and armature of relay 1 to ground. Sufficient current does not pass tlu'ough relay 7 to energize the same until the called subscriber responds at which time relay 7 attracts its armature and opens the energizing circuit for magnet 6. This magnet then releases and moves the side-switch wipers into position 41 whereupon conversation may proceed between the calling and called subscribers, talking current being; applied to the called line from relay 15. At the end of the conversation, the replacing ot' the receiver upon its switchhook at substation A returns the switches to normal in the same manner previously rci erred to.

Let it now be assumed that when substation B is called, Wiper of mechanism F is in engagement with one of the segments 7, which is electrically connected by plug f to the conducting member 7. When switch G is stepped from its norn'lal position, the otl-uorinal contact 21. is closed with the rc sult that a circuit is established. for slow-torelease relay 22 t switch l extending; from grounded battery, *inding of said. relay, upper armature and back contact of step ping relay 23, oil-normal contact 21, conductor f ineinberf, segment f and wiper f to ground. Relay 22. attracts its armatures and establishes a self-interrupting circuit for stepping relay extending from grounded battery, upper armature and front contact of relay 99 winding, upper arma- .be restored to normal.

ture and back contact of relay 23 and from thence to ground at the wiper Relay 23 operates to step the brushes of switch E overthe terminal bank of saidswitch until test terminal 24towhich'the ground at the wiper f is extended through oil-normal contact 21 and conductor 25, is reached; Relay 22, being slow'to-release,will maintain its armatures attractedduringthe stepping of the switch, The groundupon'the terminal 24. willmaintain relay 23 energized and thus prevent further stepping ot-"the switch, the same being held in its set position by means of holding pawl 26. When side-switch wipers 16 and 19 of switch C reach their third positions and ringing current through relay 7 is applied to the called line, this ringing current will also be simultaneously applied to the line of substantion D through the brushes of switch E and thus signal the attendant at said substation. The attendant after waiting a reasonabl length of time may respond by removing the receiver from its switchhook which will close a circuit through the condenser 27 at substation D and thereby increase the flow of signaling current to such an extent that relay 7 will attract its armature and the sideswitch wipers will be passed into position 4 as heretofore described. The attendant may then listen in on the circuit without disturb ing it. If the called subscriber does not respond, the attendant may, after an interval, press a key 28 to close the line circuit and establish a locking circuit for relay 29 which will maintain key 28 in its operated position. The attendant at substation D may now converse with the calling party and inform him of the absence of the subscriber at substation. B. The calling subscriber will then replace his receiver upon its switchhool: with the result that the switches employed in establishing the connection between substations A. and B will When switch C reaches normal and the oft-normal contact 21 is opened, the holding circuit for relays 22 and 23 is opened. Relay 22, in releasing its lower armature, disengages pawl 26 from teeth of the shaft E and this switch then returns to its normal position.

hat is claimed is:

1. In a telephone system, calling and called lines, an attendants position, switching means for interconnecting said calling and called lines, and means automatically operated simultaneously with said switching means during predetermined intervals for connecting said attendants position to said calling and called lines.

2. In a telephone system, calling and called lines, an attendants position, switching means for interconnecting said calling and called lines, means automatically operated during predetermined intervals for connectingsaid attendants position to said calling andcalledlines when the same] are ing means for interconnecting said calling and call'edi lines, a; switch automatically operated to connect said attendants position toysaid calling and" called lines: when the same are interconnected and means thereupon operated for simultaneously signaling said called line and attendants position.

4i. In a telephone system, calling and called lines, an attendants position, switching means for interconnecting said calling and called lines, means for connecting said attendants position to said calling and called lines when the same are interconnected, means for controlling the operation of the last-named means only during certain intervals, and means for signaling said attendants position after the same is connected to said calling and called lines.

5. In a telephone system, calling and called lines, an attendants position, switching means for interconnecting said calling and called lines, means automatically operated simultaneously with said switching means for connecting said attendants position to said calling and called lines and means for simultaneously signaling said called line and attendants position after the same are connected.

6. In a telephone system, calling and called lines, an attendants position, a connector switch operable to interconnect said calling and called lines, an automatic switch for connecting said attendants position to said calling and called lines, mechanism operable during predetermined intervals to permit of the operation of said automatic switch, means under the control of said connector switch for connecting said mechanism with said automatic switch whereby the latter is operated, and a source of ringing current at said connector switch for simultaneously signaling the called line and said attendants position when the connector and automatic switches have been connected to said called line.

7. In a telephone system, calling and called lines, an attendants position, switching means for interconnecting said calling and called lines, means for connecting said. attendants position to said calling and called lines, and time controlled means for controlling the operation of the last-named means.

8. In a telephone system, calling and called lines, an attendants position, switching means for interconnecting said calling and called lines, means operated simultaneously With said switching means for connecting said attendants position to said calling and called lines, and time controlled means for controlling the operation of the last-named means.

9. In a telephone system, calling and called lines, an attendant s position, a switch operable during predetermined intervals for connecting said attendants position to terminals of the calling and called lines, and switching means for interconnecting said calling and called lines and for controlling the movement of said switch into engagement with said terminals.

10. In a telephone system, calling and called lines, an att-endants position, switching means for interconnecting said calling and called lines, and means automatically operated to connect said attendants position to said calling and called lines.

In Witness whereof, We hereunto subscribe our names this 17th day of July A. D.,' 1919.

HENRY P. CLAUSEN. CHARLES L. GOODRUM. 

